1. Field of the Invention
The present invention relates to a rack device, and more particularly to a rack device including one or more reversible or invertible shelves.
2. Description of the Prior Art
Various kinds of typical rack devices, shelves, or construction assemblies have been developed for being constructed by the users themselves, and comprise a number of shelves to be quickly assembled or attached onto four posts, without additional fasteners.
U.S. Pat. No. 5,676,263 to Chang, U.S. Pat. No. 5,960,968 to Wang, and U.S. Pat. No. 6,036,033 to Chang disclose three of the typical rack devices each having a number of shelves that may be assembled onto four posts by the users. However, the shelves are not reversible or invertible, such that the shelves may have only one usable side.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional rack devices.
The primary objective of the present invention is to provide a rack device including one or more reversible or invertible shelves, for allowing both sides of the shelves to be selectively used.
In accordance with one aspect of the invention, there is provided a rack device comprising at least one post; a sleeve engaged onto the post, including a lower portion having an outer diameter greater than an outer diameter of an upper portion thereof; a shelf, and at least one collar secured to the shelf, including a bore formed therein for receiving the sleeve and for securing the collar and the shelf to the sleeve and the post. The bore of the collar includes two end portions and a middle portion having an inner diameter smaller than an inner diameter of the end portions thereof. The inner diameter of the middle portion of the bore of the collar is no less than the outer diameter of the upper portion of the sleeve, which permits either of the end portions of the bore of the collar to receive the upper portion of the sleeve, and the outer diameter of the lower portion of the sleeve is greater than the inner diameter of the middle portion of the bore of the collar, which retains the collar on the sleeve when either of the end portions of the bore of the collar receives the lower portion of the sleeve. Either of the sides, such as the upper and the lower sides of the shelf may be inverted, for allowing either of the sides to be arranged on the upper portion for supporting various objects.
The lower portion of the sleeve preferably includes a frustum-shaped structure. The sleeve includes a peripheral flange extended from the lower portion thereof for engaging with the collar, and for stably retaining the collar on the sleeve. The peripheral flange of the sleeve includes an outer diameter equal to that of the end portions of the collar.
The sleeve includes a peripheral rib extended from the upper portion thereof. The collar includes an inner peripheral surface for defining the bore thereof, the peripheral rib of the sleeve is engaged with the inner peripheral surface of the collar to enclose the bore of the collar.
The sleeve includes a first half including at least one notch formed therein, and a second half having at least one ear extended therefrom and engageable into the notch of the first half of the sleeve.
The post includes an outer peripheral portion having a plurality of grooves formed therein, the sleeve includes at least one stop extended therefrom for engaging with either of the grooves of the post.
The shelf includes a planar base member, and a peripheral wall member extended from a peripheral portion of the planar base member, and selectively disposed either above or below the planar base member.